U.S. Pat. No. 4,682,339, assigned to the assignee hereof, illustrates a method of coupling standing wave lasers in which two modes exist in the resonator, one magnifying as it circulates in the resonator and the other demagnifying. A portion of the output beam is sampled and injected back into the resonator mode-matched to the demagnifying mode. U.S. Pat. No. 4,841,541, illustrates the use of adjoint coupling with unstable ring resonators. These disclosures relate to unpolarized lasers.